Double-deck portable scaffold



Jan. l0, 1956 F. J. KRANE DOUBLE-DECK PORTABLE SCAFFOLD Filed March ll. 1953 [mm: Fed/WJ. Kew/v5,

i/'f #far/76g United States Patent O DOUBLE-DECK PRTABLE SCAFFLD Frank .1. Krane, Gary, Ind.

Application March 11, 1953, Serial No. 341,775

1 Claim. (Cl. 304-17) This invention relatesr to an improved portable twolevel adjustable scaffold.

An object of the invention is to provide an improved scaffold which is adapted to be carried on an overhead support, such as a crane girder, and thus eliminates the need to build up scaffolding from the iloor beneath to furnish a support for workmen.

A further object is to provide an improved scaffold which has adjustable mounting means adapted to engage a crane girder and rail to furnish a portable two-level support for workmen in the vicinity of the girder.

In accomplishing these and other objects of the invention, I have provided improved details of structure, a preferred form of which is shown in the accompanying drawing, in which:

Figure 1 is an end elevational View of a scaffold which embodies features of my invention;

Figure 2 is a front elevational view of the scaffold;

Figure 3 is a fragmentary vertical sectional view taken on line III- III of Figure 1; and

Figure 4 is a fragmentary horizontal sectional View taken on line IV-IV of Figure l.

Figures l and 2 show an overhead crane girder 10 which is supported by a series of upper and lower brackets 12 and 13 and vvertical columns 14. These brackets are mounted on additional columns 15 located behind the columns 14. The spaces between the columns 15 contain brickwork 16 forming a vertical wall. The girder is shown as formed of sections built up in the shape of an l-beam and the type of its upper flange carries a rail 17 for movably supporting an overhead crane, not shown.

The scaffold of my invention comprises four vertical tie members 18, upper and lower horizontal cross members 19 and 20, and longitudinal members 21 secured together to form a rigid structure, as by gussets 22. Preferably the tie members 18 are formed of angle irons and are sectional to permit adjustment in their length. The sections are held together by bolts 23. The upper cross members 19 carry an upper platform 24, and the lower cross members 20 carry a lower platform 25. Preferably the two platforms are formed of planks bolted to the respective cross members. Above the upper platform 24 there is a truss structure, which is formed of uprights 26 rigidly connected to the upper ends of the tie members 18, a longitudinal top member 27 rigidly connected across said uprights, and diagonal braces 28 rigidly connected between said top member and the cross members 19. Preferably the uprights 26 carry an upper guard rail 29, and the tie members 18 carry a lower guard rail 30.

The diagonal braces 28 are formed of angle irons, and one flange of each extends downwardly and inwardly to form an integral hook 31. This hook is adapted ICC to fit over the head of the rail 17. The underside of the upper platform 24 carries rollers 32 along its inner edge. These rollers are rotatable about horizontal axes and are adapted to rest on the upper face of the girder 10 alongside the rail 17. The inner tie members 18 carry rollers 33 which are rotatable about vertical axes and are adapted to bear against the outer edge of the lower flange of the girder. Preferably the legs 18 contain slots 34 in which the bearings for the rollers 33 are mounted to permit vertical adjustment of these rollers. The scaffold is supported by the hook 31 and the two sets of rollers 32 and 33. As long as a workman is standing on either platform 24 or 25, the frictional engagement between the hook and the rail holds the scaffold fixed, but otherwise the rollers enable it to be moved easily along the girder. The whole scaffold is easily moved about and installed or taken down with a suitable crane. The length of the tie members 18 can be adjusted to place the rollers 33 at the proper height for any particular girder and additional adjustment can be obtained by moving their bearings in the slots 34.

One purpose for which I have found the scaffold particularly useful is in removing or installing the brickwork 16. When it is necessary to realign the crane girder, this brickwork must be torn out and subsequently replaced. ln the absence of my scaffold, it is necessary to build up a scaffold from the floor for this purpose, obviously a costly procedure.

While I have shown and described only a single embodiment of the invention, it is apparent that modifications may arise. Therefore I do not wish to be limited to the disclosure set forth but only by the scope of the appended claim.

I claim:

A portable scaffold adapted to be mounted on an I- beam cran.: girder, which carries a rail on its top flange, comprising vertical tie members and horizontal cross members and longitudinal members interconnected to form a rigid structure, upper and lower substantially coextensive platforms carried by said cross members for supporting workmen at two levels, a truss formed of uprights, a longitudinal top member and diagonal braces rigidly interconnected and extending above said upper platform and being rigidly connected to two of said tie members and two of said cross members, hooks lxedly carried by said diagnal braces at the lower ends thereof and adapted to engage the railhead, a set of rollers carried by said upper platform adjacent said hooks and being rotatable on horizontal axes to engage the upper flange of the girdder, and a second set of rollers carried for vertical adjustment independently of said platforms by two of said tie members and being rotatable on vertical axes to engage the lower ange of the girder, said tie members being sectional to permit adjustment in their length.

References Cited in the file of this patent UNITED STATES PATENTS 514,464 Hills Feb. 13, 1894 539,200 Strub May 14, 1895 622,831 Wallach et al. Apr. 11, 1899 842,331 Palmer Jan. 29, 1907 959,278 Wells May 24, 1910 1,209,839 Hokenson Dec. 26, 1916 1,402,156 Gabrial Jan. 3, 1922 1,458,744 Brewster June 12, 1923 1,510,931 Fischer Oct. 7, 1924 2,080,015 Sneddon May 11, 1937 2,194,978 Ireland Mar. 26, 1940 

